Abstract: A discharge lamp includes a luminous bulb in which a luminous material is enclosed and a pair of electrodes are opposed to each other in the luminous bulb; and a pair of sealing portions for sealing a pair of metal foils electrically connected to the pair of electrodes, respectively. Each of the pair of metal foils has an external lead on a side opposite to a side electrically connected to a corresponding electrode of the pair of electrodes. At least one of the pair of sealing portions is provided with a reflective film on a surface of the sealing portion in a portion where a connection portion of the external lead and the metal foil is sealed. The reflective film contains a material having a reflectance larger than that of a material constituting the sealing portion.

Abstract: A method for producing a discharge lamp of the present invention includes the steps of: preparing a glass pipe for a discharge lamp having a luminous bulb portion and a side tube portion, and a single electrode assembly including an electrode structure portion that will be formed into a pair of electrodes of the discharge lamp; inserting the single electrode assembly into the glass pipe for a discharge lamp such that the electrode structure portion of the single electrode assembly is positioned in the luminous bulb portion of the glass pipe for a discharge lamp; forming a luminous bulb in which the electrode structure portion is arranged inside by attaching the side tube portion of the glass pipe for a discharge lamp to a part of the single electrode assembly; and forming a pair of electrodes in the luminous bulb by melting and cutting a part of the electrode structure portion selectively.

Abstract: A pair of electrodes (3) are provided in an arc tube (1) I/S is 20 (A/mm2) or less on a condition that an area of a cross section at a tip of the electrodes (3) is S (mm2) and an operating current between the electrodes (3) is I (A). According to this constitution, a long lamp life can be obtained without causing a rise in the lamp voltage and the blackening of the arc tube (1) by the evaporation of the electrodes while operation time becomes longer.

Abstract: The induction coil core used for an induction coil of a discharge lamp, the discharge lamp including: a bulb containing discharge gas inside; and the induction coil for generating an electromagnetic field with a frequency in a range of 50 kHz to 1 MHz inclusive in the bulb. The core is made of a Mn—Zn polycrystalline ferrite and has a Curie temperature of 270° C. or more.

Abstract: A mercury-free high-intensity discharge lamp operating apparatus includes a horizontally operated high-intensity discharge lamp including an arc tube in which a luminous material is enclosed and a pair of electrodes are arranged in the arc tube; a ballast including an alternating current generation means for supplying alternating current to the pair of electrodes; and a magnetic field application means for applying in substantially vertical direction a magnetic field having a component that is substantially perpendicular to a straight line connecting heads of the pair of electrodes; wherein mercury is not included as the luminous material in the arc tube.

Abstract: A short arc mercury lamp includes a luminous bulb enclosing at least mercury as a luminous material and a pair of electrodes opposed to each other; and a pair of sealing portions for sealing a pair of metal foils electrically connected to the pair of electrodes, respectively. The electrode central axis of one of the pair of electrodes is dislocated from the electrode central axis of the other electrode. The shortest distance d (cm) between the head of one of the electrodes and the head of the other electrode is larger than the value of (6M/13.6&pgr;)1/3 when the total mass of the enclosed mercury is M (g).

Abstract: A discharge lamp operating apparatus includes a discharge lamp; a dimmer for performing phase-control with respect to an input power source; and a ballast circuit for dimming and operating the discharge lamp in accordance with an AC voltage that is phase-controlled by the dimmer. A relationship Z2≦(Vin/Vob−1)×Z1; is satisfied, where Z1 (&OHgr;) is an impedance between an input terminal and an output terminal of the dimmer, Vob (V) is a breakover voltage of a bidirectional trigger diode that applies a trigger signal and is connected to a gate terminal of a switching element included in the dimmer, Vin (V) is an effective voltage of a commercial power source, and Z2 (&OHgr;) is an input impedance between the input terminals of the ballast circuit.

Abstract: A high-intensity discharge lamp includes an arc tube including a pair of electrodes opposed to each other therein; and a trigger wire made of a conductive material provided in an outer circumference of the arc tube. The trigger wire is turned to be in a conductive state with one electrode of the pair of electrodes when a start-up voltage is applied across the pair of electrodes, and discharge is started between the pair of electrodes in a state where an electrical field is formed between the trigger wire that is in the conductive state and the other electrode of the pair of electrodes.

Abstract: A self-ballasted fluorescent lamp 50 includes a fluorescent lamp 1 and a ballast circuit 2 for operating the fluorescent lamp. The ballast circuit 2 includes: a printed circuit board 6; a heat generating component 7 disposed on a first face 6a of the printed circuit board, which generates heat when the fluorescent lamp 1 is operated; and a semiconductor component 17 disposed on a second face 6b opposite to the first face 6a of the printed circuit board 6, and wherein the semiconductor component 17 is disposed in an area other than an area on the second face 6b corresponding to an area of the first face 6a where the heat generating component 7 is disposed.

Abstract: A fill material 201 enclosed in an arc tube 201 with an inner diameter of 10.8 mm includes ScI3, argon, and mercury. A distance between electrodes 202 is set at 2.2 mm, and a distance between the inner wall of the arc tube 201 and the electrodes 202 is set at approximately 5.4 mm, which is approximately twice the distance between the electrodes 202. The lamp of the present invention is capable of forming thin arc and thereby achieving high luminance since only the metallic elements having an ionization potential of 6 eV or higher is contained in the fill material 207. The restriction of the short distance between the electrodes serves to stabilize arc. Scandium in the fill material serves to achieve a good color reproduction characteristic.

Abstract: An electrodeless discharge lamp operating apparatus includes a transparent discharge vessel (1) in which a luminescent substance is enclosed; a coil (3) for generating an alternating electromagnetic field that discharges the luminescent substance; a power source (4) for supplying alternating current to the coil (3). The coil (3) comprises at least a magnetic material, and is disposed on an inner side than the outer side wall of the discharge vessel (1), and the luminescent substance comprises at least a rare gas, and does not comprise mercury.

Abstract: Relatively uniform high frequency energy can be applied to a planar or linear discharge space and a more uniform discharge can be produced by using an electrodeless discharge energy supply apparatus which comprises a surface wave transmission line 11 for exciting a surface wave by a high frequency, the surface wave transmission line 11 being formed from a conductive material having a periodic array of corrugations 14, wherein using the surface wave produced in the vicinity of the surface wave transmission line 11, energy necessary to produce an electrodeless discharge is supplied to an electrodeless discharge tube 12.

Abstract: A short-arc high-pressure mercury vapor discharge lamp includes a pair of electrodes in an arc tube and encloses mercury, a rare gas, and so forth in the arc tube. The lamp is so constructed as to be operated at a lamp current of, for example, about 1.5 A or higher, or at a lamp voltage/lamp current ratio of about 37.5 (V/A) or lower. In addition, the distance between the electrodes, and the like are set so that the rated power per unit arc length P/d≧88 (W/mm) and the tube wall loading Pw (rated power P/internal surface area of the arc tube)≦1.0 (W/mm2). Thus, a lamp is constructed having, even with a relatively low lamp voltage, a high lamp power of, for example, 125 W or higher, having a short arc length and a high luminous flux per unit arc length, and furthermore being one in which damage to the arc tube does not occur.

Abstract: The present invention discloses an operating apparatus of discharge lamp comprising an AC/DC converter means for converting an ac voltage into a dc voltage, a DC/AC converter means for converting a dc output voltage of the AC/DC converter means into a high frequency ac voltage, a discharge lamp coupled to an output terminal of the DC/AC converter means, and a controller means by which the output of the DC/AC converter means is made variable according to an integrated value based on a half cycle of the ac voltage.

Abstract: A discharge lamp operating apparatus includes a discharge lamp and a driving circuit of the discharge lamp. The driving circuit can vary power to be supplied to the discharge lamp and has a function to turn off the discharge lamp at a supplied power value above a supplied power value at which unstable discharge occurs in the discharge lamp.

Abstract: In a high intensity discharge lamp, at least one of an arc bend amount and an apparent width of arc is controlled by a simple configuration at low cost. A high intensity discharge lamp system 110 has a high intensity discharge lamp 111 and an operating circuit 113 for driving the high intensity discharge lamp 111. In the high intensity discharge lamp 111, a rare gas and a filling material 136 containing a metal halide as a light generating substance are enclosed in the arc tube 121 provided with a pair of electrodes 122a and 122b. The lamp system is disposed such that the line connecting the electrodes 122a and 122b is horizontal, and by applying a magnetic field having a vertical magnetic flux thereto and by varying the frequency of alternating current for driving the high intensity discharge lamp 111, at least one of an arc bend amount and an apparent width of arc can be easily controlled.

Abstract: An image projector has a lamp unit 23 having a high-pressure mercury vapor discharge lamp 21 and a parabolic mirror 22. To the high-pressure mercury vapor discharge lamp 21, a driving system 24 applies an alternating voltage such that wandering of a cathode luminescent spot generated in the vicinity of a tip of each of the discharge electrodes of the high-pressure mercury vapor discharge lamp 21 is suppressed, the frequency being within the range of 20-42 kHz. This construction allows to prevent flicker in a projected image of a liquid crystal projector and the like, and therefore achieves high quality in the projected image.

Abstract: A high-intensity discharge lamp includes an arc tube including a pair of electrodes opposed to each other therein; and a trigger wire made of a conductive material provided in an outer circumference of the arc tube. The trigger wire is turned to be in a conductive state with one electrode of the pair of electrodes when a start-up voltage is applied across the pair of electrodes, and discharge is started between the pair of electrodes in a state where an electrical field is formed between the trigger wire that is in the conductive state and the other electrode of the pair of electrodes.

Abstract: The present invention relates to a lamp device using a high-pressure vapor discharge lamp, particularly to an improvement for controlling the influence of the generation of heat, which accompanies an increase in lamp power and a reduction in the size of a reflector. A lamp device of the present invention comprises a discharge lamp having an arc tube enclosing luminescent materials and having a pair of opposing electrodes disposed therein and a pair of sealed portions extending from the arc tube; a reflector which reflects light radiated by the discharge lamp; a transparent member covering an open end of the reflector and accommodating the discharge lamp in a space between the transparent member and the reflector; and means for preventing an excessive temperature rise wherein the temperature rise of welded parts of wiring members electrically connected to the electrodes of the discharge lamp is restricted.

Abstract: The present invention provides a long-life discharge lamp by removing the causes of lowering the service life of the discharge lamp owing to quartz glass constituting the discharge lamp and a gas sealed therein, and also provides a discharge lamp production method wherein the mixing of impurities affecting the service life of the discharge lamp is prevented. In the discharge lamp the content of hydrogen, oxygen and their compounds existing in the light-emitting portion is such that the maximum intensity of the light-emitting spectral intensities of the above impurities is {fraction (1/1000)} or less of the intensity of the main light-emitting spectrum of the noble gas when glow discharge occurs by supplying a current of 3 mA, and also the content of OH groups included in the quartz glass of the sealing portions is 5 ppm or less by weight.